The present invention is directed to a method for improving presentation of results of a search in a structured database. More specifically, the present invention is directed to a method for ranking the results of a search in a structured database and presenting the results in ranked order.
It is well known to search for records or documents in a structured database. Such searches typically take the form of specifying one or more attribute/value pairs for some of the attributes of the database schema. Presently it is known to perform such searches on the World Wide Web (WWW). As an example, Rainbow Pages (http://rp.control.att.com/reso.html) can retrieve all of the U.S. residential records matching a given attribute/value pair such as name=J. Doe.
Search engines for structured databases typically use conjunctive strategies for retrieving documents. For instance, if the search query includes two or more attribute/value pairs, then the search engine only returns those documents, or pointers to those documents, which satisfy all of the attribute/value pairs specified in the query. If one of the attribute/value pairs is not found in a given document, then that document is not considered to be a proper response to the query and is disregarded. As a consequence, the results to a search request can be somewhat limited in that the requester will only be provided documents that exactly match the search query.
It is known in the context of searches for unstructured documents on the web to provide a ranked retrieval using a set of key words rather than using the Boolean conditions typically utilized in searches of structured databases. In searches for unstructured documents on the web, given a set of key words k as the query, documents that match any of the key words in k are part of the answer set. As a consequence, the requester can then analyze the retrieved documents and determine which are the most pertinent even where no one of the documents completely satisfies the query.
It would be advantageous if a search of a structured database would provide similarly broad ranges of responses where no one of the documents necessarily matches all of the attribute/value pairs set forth in the search query.